A plan of 1826 shows nine embrasures on the Right Face and seven on the Left Face with four on each flank. The 1834 Armament’s List, however, recorded that King’s Bastion mounted twenty-six guns: two brass 10-inch howitzers, fourteen 32-pdrs and ten 24-pdrs.
In 1840, Major General Sir John Jones KCB was sent to Gibraltar by the Master General of the Ordnance to make a detailed survey of the defences. He remained there until June 1841 and his report run to around 250 pages. The details concerning the King´s Bastion were as follows:
SEA DEFENCES OF THE TOWN: Towards the sea some very considerable reforms are indispensable in the Town defences, and I propose to replace the existing thin, decayed, ill-traced and ill flank scarps on the right and left of the King's Bastion by solid scarps, well flanked, and so traced as to aid in general the defences of the front. It is also proposed to cut off or retrench the King's Bastion which, from its very prominent position is much open to surprise and to be beaten down by cannonade. It is to be recollected that along every other part of the Rock a powerful force only can have a chance of success; but within the Town the entrance of a very small body might lead to the capture of the place. I have therefore endeavoured to strengthen the sea defences as far as their position and a due regard to expenditure admit; and although my views have been impeded, and my projects distorted by the mutual interference of private interests almost to the very parapets, still I feel assured that the new defences will prove equal to the object for which they are planned, and that with due vigilance the Town will have nothing to apprehend from external force.
The King's Bastion is the great bulwark and prominent feature of the defence of the sea line of the Town: It is a most creditable work, well planned and well built, but from its advanced position and the number of its embrasures, it is very likely to be selected as the object of s serious cannonade or stealthy surprise, and therefore should have the support of some interior work to give it that full security which its importance demands. It will scarcely be credited that neither at this bastion, nor at any point on the sea defences, does any provision exist for the residence of a Captain or Subaltern, and they are generally so distantly lodged that the place might be entered and the troops put into utter confusion before any company officer could reach the spot to direct their movements. Casemates have therefore been introduced under the rampart of the projected defensive line across the Gorge and caponniers are necessary for the purpose of scouring the dead portions of the scarp of the bastion caused by the projecting orillons.
These recommendations resulted in the construction of new casemated retrenchment block in the gorge immediately behind the King’s Bastion which replaced the already decommissioned 18th Century casemates within the King’s Bastion itself. These new accommodations became Married Quarters whilst the Officer’s Quarters and Mess House was constructed across the road: this last building would later become St. George’s and St. Mary’s School respectively and is presently the premises of the Casino Calpe. Photographs taken in the 1870’s show that this gorge was much wider than what remains today, with the ramp leading into the gorge directly in line with King’s Street rather than parallel with Line Wall as it is today. Modern road surfacing has covered much of the old gorge in order to straighten and widen the Line Wall Road for vehicular traffic.